Abstract
Background: Researchers often consider mixing modes for data collection to increase response rate. However, it is possible that people respond differently when asked sensitive questions (like questions about depression) by mail compared to phone.
Methods: A random sample of 4000 adolescent health plan enrollees (ages 13–17 years) were invited to participate in a brief survey examining exercise, sedentary behaviors, and depressive symptoms. Mailings were directed at parents and included an invitation letter, a consent form, survey, and a $2 pre-incentive for the youth. Parents were instructed to complete the consent form and give the survey to their child to complete and return. Non-responders were sent a second survey. Among remaining non- responders, 60% of the adults were phoned, asking them to review and sign the consent form and to ask their child to complete the screener. Forty percent of remaining non-responders were phoned asking the adults’ permission to complete the screener with the child by phone. In a second study, 9,838 adults with a history of diabetes or heart disease were invited to participate in a randomized controlled trial. The initial contact was a mailed 5-item survey that included a depression (PHQ2) screener and eligibility questions, along with a study information sheet and a $2 pre-incentive. Approximately 12 days later, non-responders were sent a second survey, and 10 days later, non- responders were called to complete the screener by phone.
Results: Data collection is being completed as this abstract is submitted. This poster will examine whether there are differences in depression scores among those who are early responders (complete after one mailing), those who complete after a second mailing, and those who complete by telephone. We will also examine whether there are demographic differences at each step. In addition, we will demonstrate the increases in response rate by adding a phone call to complete a mailed survey.
Conclusions: This poster will indicate whether this mixing of modes compromises data quality or produces different responses than if only one mode was used.
